body{
    display: flex;
    /* 主轴为垂直方向，起点在上沿 */
    flex-direction: column;
}
.top{
    height: 50px;
    line-height: 50px;

    .icon-arr-right{
        font-size: 20px;
        margin-left: 10px;
    }
}
.con{
    flex: 1;
    overflow-y: scroll;
}
